Systems and methods for manipulating the pitch and/or tilt of a trailer relative to a supporting surface. A trailer leveling system includes one or more telescopically adjustable support assemblies that are constructed to be pivotably connected to a frame of a trailer. Each support assembly includes a post that is pivotably connected to a trailer frame. A rack is formed along at least one side of the post. A tube slideably cooperates with the post and supports a pawl that cooperates with the rack to allow translation of the tube relative to the post in a first direction and selectively prevent translation of the tube relative to the post in the opposing direction.